Another option might be to purchase a Mojo-Sight, if they still are available..

It is a rear peep that replaces the original open rear sight with no gunsmithing/alteration necessary...

I bought one for my M48 Yugo and it works well...It is adjustable for elevation, so there's a good chance you won't have to replace the front blade on your mauser.. It's also a superior sight picture ,at least for my old eyes, to the standard mauser V notch....